There are many situations where it is important to stabilize a slope, or non-sloping ground. Steep, unstable slopes may be created during certain types of construction, such as freeway widening, golf course construction, or other types of construction where the ground is altered. These slopes are not naturally occurring, but instead are the result of human activity. These slopes often need stabilization, even when there are no signs of slope failure.
Similarly, it may be desirable for safety reasons, to strengthen certain slopes that are relatively stable, whether naturally occurring or the result of human activity. For example, it is prudent to stabilize slopes behind power plants, or slopes at the base of dams or bridges, even when the slope does not appear to be at or near failure. Also, non-sloping ground adjacent to water may benefit from stabilization.
Most of the research and work on slope and ground stabilization relates to stabilizing landslides. An effective, relatively small-scale method for stabilizing slopes created by human activities, for stabilizing slopes for safety reasons, or for stabilizing non-sloping ground is needed.
Research on mitigation techniques for shallow, colluvial landslides has seen some interest from the geotechnical community in the past 20 years, although most research has been performed on the predictive analysis of these types of slides (e.g. Aubeny and Lytton, 2004; Cho and Lee, 2002; Collins and Znidarcic, 2004; Iverson, 2000). Predictive analysis techniques are an important aspect of understanding slope stability behavior. However, it may be desirable to stabilize ground or slopes, even when there is no direct prediction of failure, for safety reasons.
Existing methods of landslide mitigation have been summarized by Rogers (1992). They include excavation and recompaction, conventional retention structures, subdrainage, soil reinforcement using geomembranes and geosynthetics, mechanically stabilized embankments, and combination mechanically stabilized retention structures.
Unfortunately, most of these mitigation options are often not useful, mainly due to economic considerations. Retention structures, soil reinforcement options, mechanically stabilized embankments, and combination structures all require large volumes of earthworks in addition to comparatively expensive and time consuming installation methods. The present invention minimizes the need for large machinery and thereby allows slope and ground stabilization around existing homes, and in other areas with limited access.
Others, such as Ito et al. (1981, 1982), have addressed rotational landslides. These deep landslides have been mitigated with extremely long (25 to 100 feet) columns (piles) placed in a portion of the potential slide area, generally at the toe of the slope to lock down the base of the potential slide. However, these long, heavy piles are often prohibitively expensive. The present invention allows for locking down a slope or ground by placing relatively small, lightweight plate piles throughout the target area.